As is known, railway and subway carriages each have a body or shell provided with an underframe which defines the base for the inner floor of the carriage itself. Normally, the underframe must meet technical standards and specifications relating to fire resistance, particularly resistance to fire (REI) of 30 minutes. To meet these requirements, especially when the underframe is made of aluminium, its lower surface is coated with intumescent paint, applied by using spraying technology.
This solution, though widely used, must be performed in specific areas equipped for painting operations and requires high line crossing times in the production cycle.
US2014238262 describes a solution according to the preamble of claim 1, where the fire protection system is defined by a panel with insulating material fixed to the underframe.